A thief took medication and cash from a terminally ill man as he slept in his home, police said.
The 75-year-old victim, who has cancer, had recently been discharged from hospital and was resting in his living room at his home in Dixon Green, Dudley, when the thief struck.
It was only when he woke up that he realised money and his morphine-based medicine had been stolen in what West Midlands Police called an "extremely cruel and callous" attack.
Susan Williams, the daughter of the burgled pensioner, said: "I can't believe anyone would do this to my dad; he is suffering from cancer and is terminally ill.
"It has set him back and he has had to be readmitted to hospital.
"I am appalled. How could anyone do this to a dying man? It would have been obvious that he was ill. For someone to see him sleeping and then search around him and steal his cash and medication is just too upsetting."
Detective Constable Ross Evans, from Dudley Investigation Team, said: "The man is elderly and very poorly and for someone to prey on such a vulnerable person makes this extremely cruel and callous."
Officers said the burglary took place between 1pm on November 2 and 9.15am on November 3 and they are analysing CCTV for clues.
Anyone with information is asked to call police on 101 or Crimestoppers anonymously on 0800 555111.